Compressors, turbines, and various turbocharger arrangements are frequently used to improve the efficiency of internal combustion engines. Introducing turbines into the exhaust gas flow can reduce the temperature of the exhaust gas and may reduce the effectiveness of downstream emissions controls, such as catalytic converters and other aftertreatment devices frequently used to reduce engine emissions. In particular, a significant amount of emissions are attributable to engine operations at lower temperatures upon startup, commonly referred to as cold start emissions. Accordingly, it is desirable to provide methods and systems for reducing cold start emissions.